1. Field of the Invention
This invention relates to an actuator used, for example, for door locking system which may lock or unlock a door automatically.
2. Description of The Prior Art
Heretofore, there has been used an actuator as shown in FIG. 7 of the present application corresponding to Japanese Patent Disclosure No. 60-59278/851.
An actuator 100 shown in the figure is fitted with a motor 102 in a motor fitting pat 101a provided in casing 101. The motor 102 is installed in the casing 101 by pressing a bar 103 onto an end cover 102a of the motor 102 and driving screws 104 through the bar 103 into the casing 101.
A pinion 105 is force-fitted onto the shaft 102b protruding from said end cover 102a, and is meshed with a larger gear part 106a of an intermediate gear 106 which has the larger part 106a and a smaller gear part 106b as one body and supported rotatably by an intermediate shaft 107.
A sector wheel 109 is fixed to an output shaft 108 supported rotatably by the casing 101, and the smaller gear part 106b of the intermediate gear 106 is meshed with said sector wheel 109.
Additionally, a swing arm 110 is fixed to the output shaft 108 on the outside of the casing 101 so as to transmit the output of this actuator 100 to the outside.
Upon supplying a prescribed electric current to the motor 102 through a terminal 102c or 102d, the shaft 102b of the motor 102 rotates in the forward or reverse direction.
By the rotation o the shaft 102b of the motor 102 in forward direction, the power o the shaft 102b is transmitted to the sector wheel 109 from the pinion 105 through the larger gear part 106a and the smaller gear part 106b of the intermediate gear 106, and the sector wheel 109 engages the damper 111 provided on the casing 101. The sector wheel 109 engages another damper 112 when shaft 102b of the motor 102 rotates in the reverse direction. The sector wheel 109 rotates oscillatively in the range in which the sector wheel 109 is out of contact with either damper 111 or 112.
Thereby the swing arm 110 functions, a door (not shown) is locked and unlocked by getting a door lock rod 113 up and down which is connected with said swing arm 110.
However, in the conventional actuator 100 as mentioned above, because the motor 102 is installed in the casing by pressing the bar 103 onto the end cover 102a and driving the screws 104 through the bar 103 into the casing 101 after fitting the motor 102 into the motor fitting pat 101a provided in the casing 101, there is a problem in that it is difficult to incorporate the motor 102 into the casing 101. Furthermore, there is another problem in that it is not possible to make the actuator 100 compact since the longitudinal direction of the shaft 102b and the direction of the thickness of the actuator 100 are the same. As a result, there has been a demand to provide an actuator which is compact and easy to incorporate into the casing 101.